There is no best martial art. There is a martial art which is better for you depending on the type of person you are (assuming that you actually stick with it).
I study Aikido. I find it better that karate, kung fu, etc because its a defensive art. Some people will automatically dismiss it though because it deosn't appeal to them.

If you want to study a martial art dont ask for people's biased opinions, go out to the local clubs in your area and either watch a session or ask if you can do a 'taster' session to get the feel of it and see if you like it or not.